Aaron Hernandez seemed to have it all. He turned a hardscrabble childhood into superstar NFL dreams. In 2012 he was on one of the all-time best teams in the NFL and was armed with a new $40 million contract extension. But then it all fell apart when he was arrested for the 2013 murder of semi-pro linebacker Odin Lloyd in North Attleboro, Massachusetts. He was convicted of murdering Lloyd in 2015 and in April 2017, Hernandez committed suicide in a Massachusetts prison where he was serving a life sentence. He was 27.

"I believe this is the most fascinating, complicated and troubling crime story of our times," Patterson says. "And you don't know the half of it yet."

Patterson and "48 Hours" take viewers on a journey through Hernandez's life -- as a child growing up in Bristol, Connecticut, where football glory got him into college and then to the NFL. But, despite the on-field accolades, as Patterson reports, he could never outrun his history, including the impact the death of his father had on him and his other personal demons, which remained hidden behind the mask of a celebrity football player. In addition to being charged and convicted of killing Lloyd, Hernandez was also charged and acquitted of killing two others.

"You hear stories about the fall from grace," says Urban Meyer, who coached Hernandez at the University of Florida. "And this might be one of the most tragic of all time."

Off the field, Hernandez hung out with a bad crowd and used drugs, police say. After his death, doctors learned, the countless hits he took playing football may have caused Chronic Traumatic Encephalopathy, better known as CTE, a degenerative brain disease found in people who have suffered repeated trauma to the head. The illness can't be identified until the person has died. In November 2017, researchers at Boston University revealed that Hernandez had the most severe case of CTE they'd ever found in a brain of someone his age, which, they said at the time, would have impacted his decision-making, inhibition of controlling aggression, emotional volatility and rage behaviors.

"The greater he was at his job the more damage that he sustained," says attorney Linda Kenney Baden.

"He wasn't an evil man. No he wasn't. He was a sick man," Dr. Bennet Omalu, the first to identify CTE in football players says of Hernandez.

Patterson's new book, "All-American Murder: The Rise and Fall of Aaron Hernandez, The Superstar Whose Life Ended on Murderers' Row" is due out on Jan. 22. Click here to read an excerpt.

Little, Brown and Company

Patterson has been reporting for a new book on Hernandez' story since the former gridiron great hung himself with a bedsheet, "All-American Murder," due out Jan. 22, 2018, from Little, Brown and Company. Hernandez's death, Patterson says, didn't end the story; in fact, it "opens up a whole new arena of conflicts and questions."

Where did Hernandez go wrong? How could he not use his success in the NFL to leave the streets behind? And what led a man who seemingly had a huge future ahead of him to kill?

"Involved in a murder? I could see that. He fooled a lot of people," says Rapoport.

Hernandez had been appealing his conviction at the time he died. Because of an obscure law, once he died, his conviction was technically vacated.

Patterson and the team at "48 Hours" report on Hernandez's life and how he ended up convicted of murder by taking viewers to his hometown, to the streets that hardened him, to the home he bought after hitting the NFL, and the prison where he died. Patterson asks the question: What role did CTE play in Hernandez's life as an adult and did it lead to his suicide? Patterson also talks with people who knew him, who covered him, those who hung out with him, and even one who was threatened by him. Together, they tell the story of how someone described as likeable and well-behaved in high school could turn into a street criminal with an NFL paycheck.